Tap Water Quality Report
Tap water quality in HONOLULU-WINDWARD-PEARLHARBOR, Hawaii
Tap water in HONOLULU-WINDWARD-PEARLHARBOR, Hawaii receives a grade of B (85/100) from TapWaterSafety.org. It's served by HNL-WINDWARD-PEARL HARBOR. The most significant water quality concerns are: Chromium (hexavalent) significantly above health guideline; Perfluorohexane sulfonate (PFHXS) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in HONOLULU-WINDWARD-PEARLHARBOR's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving HONOLULU-WINDWARD-PEARLHARBOR.
Chromium (hexavalent) significantly above health guideline
Moderate concernChromium (hexavalent) detected at 1.78 ppb, 89x above the EWG health guideline of 0.02 ppb.
Perfluorohexane sulfonate (PFHXS) significantly above health guideline
Moderate concernPerfluorohexane sulfonate (PFHXS) detected at 0.034 ppt, 34x above the EWG health guideline of 0.001 ppt.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 3.76 ppb, 25x above the EWG health guideline of 0.15 ppb.
EPA compliance record
Official U.S. EPA records for HNL-WINDWARD-PEARL HARBOR (system ID HI0000331) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Recommended filters for HONOLULU-WINDWARD-PEARLHARBOR
Filters matched to the specific contaminants in HONOLULU-WINDWARD-PEARLHARBOR's water supply.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts like TTHM. Look for NSF/ANSI 53 VOC or chloroform reduction.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in HONOLULU-WINDWARD-PEARLHARBOR's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Chromium (hexavalent) Heavy metal |
1.78 ppb | 0.02 | — | — | — | — | — | 89× over |
| Perfluorohexane sulfonate (PFHXS) PFAS |
0.034 ppt | 0.001 | 10.0 | — | — | — | — | 34× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
3.76 ppb | 0.15 | 80.0 | 100 | — | — | — | 25× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
0.918 ppb | 0.06 | — | — | — | — | — | 15× over |
| Dibromoacetic acid Disinfection byproduct |
0.418 ppb | 0.03 | — | — | — | — | — | 14× over |
| Bromochloroacetic acid Disinfection byproduct |
0.136 ppb | 0.02 | — | — | — | — | — | 6.8× over |
| 1,2,3-Trichloropropane Other |
0.00395 ppb | 0.0007 | — | — | — | — | — | 5.6× over |
| Bromoform Disinfection byproduct |
2.77 ppb | 0.5 | — | — | — | — | — | 5.5× over |
| Nitrate and nitrite Inorganic |
0.414 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 3.0× over |
| Nitrate Inorganic |
0.41 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 2.9× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
0.242 ppb | 0.1 | 60.0 | 60 | — | — | — | 2.4× over |
| Trichloroacetic acid Disinfection byproduct |
0.0661 ppb | 0.1 | — | — | — | — | — | Below guideline |
| Dibromochloromethane Disinfection byproduct |
0.0658 ppb | 0.1 | — | — | — | — | — | Below guideline |
| Radium, combined (-226 and -228) Radiological |
0.03 pCi/L | 0.05 | 5.0 | — | — | — | — | Below guideline |
| Vanadium Other |
11.3 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Dichloroacetic acid Disinfection byproduct |
0.0968 ppb | 0.2 | — | — | — | — | — | Below guideline |
| Chlordane Other |
0.0137 ppb | 0.03 | 2.0 | — | — | — | — | Below guideline |
| Chlorate Disinfection byproduct |
29.1 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Heptachlor epoxide Other |
0.000546 ppb | 0.006 | 0.2 | — | — | — | — | Below guideline |
| Barium Heavy metal |
5.02 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Manganese Heavy metal |
0.106 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Strontium Radiological |
0.107 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| 1-Butanol Other |
0.378 ppb | — | — | — | — | — | — | Below guideline |
| Chromium (total) Heavy metal |
1.63 ppb | — | 100.0 | — | — | — | — | Below guideline |
| Dieldrin Other |
0.0114 ppb | — | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.00981 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from HNL-WINDWARD-PEARL HARBOR.
General Contact
Treatment Plant
ZIP codes served
HONOLULU-WINDWARD-PEARLHARBOR's public water systems serve the following ZIP codes: